1. Field of the Invention
The present invention in general, relates to heaters of the type in which liquid fuel is ignited to produce heat energy which, by means of a deflector or deflectors, is subsequently radiated in a desired radiation direction. More particularly, the invention relates to such a heater utilized especially to heat the bole and middle portion of a tree and in which deflector means are provided to direct radiant heat energy outwardly from the heater along a horizontal and angularly upwardly oriented plane.
2. The Prior Art
Already well known in the art are orchard heaters in which liquid fuel is combusted within a combustion chamber and the thus generated heat is radiated outwardly from the heater. Typically, when it is desired that certain portions of a tree, or the like, be heated, deflector members are utilized to beam the heat rays at such desired portions to be irradiated. One such prior art heater has been disclosed in U.S. Pat. No. 3,809,057 to Frost. The heater described in this patent comprises a dome like combustion chamber which has an exhaust port and conical radiant heat deflector which functions to direct rays of radiant heat deflector which functions to direct rays of radiant heat horizontally directly to the bole of the tree. To provide combustion of liquid fuel, a burner assembly is provided at the base of the combustion chamber and which comprises a tubular fuel line which has a spiral portion which forms the burner. An asbestos wick is positioned within this spiral portion and with a burner aperture provided at the end of the spiral. An intermediate chamber is located within the fuel line to relieve back pressure formed therein. The chamber, in the arrangement shown, is filled with steel wool and includes a capillary tube extending therethrough. The capillary tube includes a plurality of capillary holes formed therein which function to permit the fuel to pass therethrough from the chamber to insure the continuous flow of fuel to the burner at all times.
Although this art device provides that generated heat is directed to the bole of a tree, it has the disadvantage that heat emanating from the burner at the bottom of the dome-shaped combustion chamber also, and to quite a substantial extent, irradiates the upwardly inwardly converging conical surfaces of the chamber and which surfaces, in turn, radiate the heat in an unwanted upward direction, which presents a loss of heat energy. In addition, the radiant heat deflector which has the apex of its cone-shaped structure oriented downwardly toward the open upper end or exhaust end of the dome-shaped combustion chamber, does not solely deflect the rays of heat in a radially outwardly horizontal pattern, this for reasons that heat rays impinging upon the conical surfaces of the cone-shaped deflector are not subjected to a 90.degree. deflection by the deflector, rather the cone-shaped deflector will deflect the heat rays at a random angle depending upon the angle at which the heat rays strike the deflector. Assuming, arguendo, that the above discussed prior art device is capable of radiating heat in a horizontal plane, such radiation in a single direction is insufficient in those cases where, for instance, other portions of a tree are to be irradiated.